The prohibition of Hosa’ah, carrying in a public domain, is less restrictive on Yom Tob on Shabbat. The Rema rules in accordance with Tosafot that any carrying "L’sorech," for a specific need on Yom Tob, is permitted. Maran (Siman 518) rules that it is permitted to carry even for no purpose whatsoever. Hacham Bension understands this to mean that one may carry any item that is not Mukseh, without having to justify the purpose or the need. However, since the Biur Halacha questions whether this is in fact the intent of Maran, Hacham Bension rules that one should try to follow the ruling of the Rema and only carry when there is a specific purpose.
One application of this discussion is carrying a Shofar in the public domain on Rosh Hashana in order to blow it for a woman. Although women are not obligated in the Misva, they have already accepted upon themselves the custom to hear Shofar and get a Misva for doing so as "Eno Mesuva V’Oseh." Therefore, Hacham Ben Sion in his Ner Lesion (Vol. 3) rules that this is considered a bona fide need and even according to the Rema the Shofar may be carried. The same principle would apply to carrying a Shofar to blow for a minor who is only obligated M’Drabanan (Rabbinic Law).
SUMMARY
One should be strict and only carry on Yom Tob for a specific need of Yom Tob.
